This invention relates in general to electrostatographic reproduction apparatus employing corona chargers, and more particularly to a device for collecting contamination products and ozone from a corona charger of an electrostatographic reproduction apparatus.
In modern high speed/high quality electrostatographic reproduction apparatus (copier/duplicators or printers), a latent image charge pattern is formed on a uniformly charged dielectric support member. Pigmented marking particles are attracted to the latent image charge pattern to develop such image on the support. The dielectric support is then brought into contact with a receiver member and an electric field applied to transfer the marking particle developed image to the receive member from the dielectric support. After transfer, the receiver member bearing the transferred image is transported away from the dielectric support and the image is fixed to the receiver member by heat and/or pressure to form a permanent reproduction thereon.
In certain process steps for the electrostatographic reproduction apparatus, such as for example uniformly charging the dielectric support, detacking the receiver member from the dielectric support, or cleaning the dielectric support, it is common practice to employ corona chargers. However, corona chargers have a tendency to produce harmful gases such as ozone and nitrogen oxides. The adverse effects of ozone on equipment and humans has been well established. The need for control of the ozone emissions is especially critical in the area of consumer products such as reproduction apparatus since the operator is usually unaware of the hazards. Further, nitrogen oxides have been shown to be deliterious to dielectric supports causing undesirable image defects in the copies being reproduced by the reproduction apparatus.
Devices have been proposed for removing corona charger generated harmful gasses from electrostatographic reproduction apparatus (see for example U.S. Pat. Nos. RE 30,897, reissued Apr. 6, 1982, in the names of Yamamoto et al, and 4,143,118, issued Mar. 6, 1979, in the name of Laing). Such devices are relatively large, and have not been designed to be completely effective for their intended function. That is, they tend to draw additional contaminants from inside the reproduction apparatus into the charger where such contaminants can contaminate the charger. Further, in modern reproduction apparatus where space within the apparatus housing is at a premium, it may not be possible to economically employ such devices. In order to overcome space limitations, a unique environmental control apparatus of compact configuration is described in U.S. patent application No. 625,190, filed Dec. 10, 1990, in the name of Creveling.